1. Field of the Invention
The invention relates to foam-type coating removers and somewhat more particularly to an improved composition and method for removing or stripping paints, varnishes, lacquers and other coatings and/or finishes from various surfaces by utilizing a foam-type coating remover which is characterized by relatively high persistency and relatively low volatility. 2. Prior Art
The removal or stripping of paint, varnish, lacquer and other coatings or finishes from a surface presents a variety of problems to those in the art, particularly where relatively large surfaces are involved having horizontal and vertical portions. The removal of special coatings, such as coatings based on polyamide epoxy resins has introduced even further complications because of the special characteristics of such coatings which may require more volatile solvents as well as a relatively long exposure to the reacting solvent in order to obtain adequate removal. Known coating removers are not well suited to these difficult coating removal situations, since they have numerous disadvantages, such as being toxic, flammable and/or non-biodegradable or being too volatile or lacking sufficient persistency or being difficult to dispense and/or removed.
Although N-methyl-2-pyrrolidone is known to be effective as a stripping agent for paints, varnishes and other finishes based on cellulosic, vinyl and acrylic resins, however, to the best of our present knowledge, N-methyl-2-pyrrolidone has not heretofore been used or suggested for use as a reactive solvent in a foam-type coating remover.
N-methyl-2-pyrrolidone is also known for use as an effective stripping agent in removing chromate primers and epoxy coatings when a relatively large amount thereof (65%) is combined with methylene chloride and other usual agents. However, such a formation is expensive and the use of methylene chloride is disadvantageous in that methylene chloride is toxic and is non-biodegradable so that any formulation utilizing this material must be handled with care so as not to injure the operator or the environment.